1. Field of the Invention
The present invention relates to a recording apparatus, a detection method, and a storage medium.
2. Description of the Related Art
An inkjet printing apparatus performs recording by discharging a plurality of ink drops from an inkjet head onto a recording medium. It is expected that each of the plurality of ink drops is discharged in a predetermined amount of discharge. Various errors included in the printing apparatus, for example, manufacturing errors of ink or an inkjet head may cause a difference of the volume of ink drops (actually discharged from the ink jet head) from the predetermined amount of discharge, possibly affecting the recording density. To cope with this problem, measures has been taken to record test patterns with the printing apparatus, detect the recording density by using a sensor including a light emitting element and a light receiving element, and correct image data to achieve a predetermined recording density. The optical characteristics of the light emitting element and the light receiving element vary for each sensor. Since a reading result of the sensor in optical characteristics correction affects the density of a print product, it is important to guarantee in advance the reading accuracy of the sensor. Therefore, U.S. Patent Application Publication No. 2003/0011767 discusses a spectrometric apparatus for performing sensor calibration by using a white calibration plate. Further, Japanese Patent Application Laid-Open No. 2004-85376 discusses a technique for detecting dirt on such a white calibration plate. The technique discussed in Japanese Patent Application Laid-Open No. 2004-85376 measures the optical density of the white base of a test chart and then distinguishes dirtiness of the white calibration plate based on the test result.
However, this technique has a problem of complicated operations involving test chart recording.